87 5ktq Co problem

["ARESCO, Inc." <aresco@nfinity.com>]

I need a little help.

I've got a 87 5ktq I've had since new.  It now has 223,000 miles on it yet.  No turbo modifications or any modifications of any kind have been made on it.  My problem is that over the past few years, the car does not accelerate smoothly.  It always feels like if 'flattens out' or has a tendency to 'kick and buck' all the way up to red line.  It's not a problem on light to moderate acceleration but when you begin to go to heavy acceleration and get into higher RPMs (not necessarily floored), this problem occurs.  I've had it to multiple Audi mechanics and the dealer, but nobody has fixed the problem for good.  However I've noticed that when they adjust the CO in the car, it runs very well for a few days.  Then gradually the problem comes back.  Every time I have the CO checked, it's off.  I've been told by the dealer that this car is very sensitive to the CO adjustment.  

Is there something that could be wrong that would cause the car to keep losing the CO adjustment (perhaps a bad regulator, etc.)?  Or is this a problem with Audi's that nobody can fix for good and I have to live with it (like they have been trying to tell me)?  

Secondly, I have an intermittent problem that has just started.  Twice over the past two weeks, the car will crank over when you turn the key, but the engine will make no effort to start.  This has happened once on a hot engine (car was shut off for 30 seconds then wouldn't re-start), and the other time when it was relatively cold (sat for about 2 hours in 35 Deg F weather).  If you come back later, it will start just fine.  The car has never died while the engine was running, which eliminates a lot of things.  Any thoughts?

Thanks,

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John F. Lingelbach                                             

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